When components are mounted on a circuit board or the like by a component mounting machine, a large component and a component which has a special shape less likely to be sucked by a suction nozzle are clamped and carried by chuck pawls of a chuck device. Although most chuck devices clamp the component from both sides with a pair of (two) chuck pawls, that disclosed in PTL 1 (JP-UM-A-6-24882) has two pairs of (four) chuck pawls placed at an interval of 90° and allows the two pairs of chuck pawls to be put into a clamping operation at the same time so that the component is clamped in four directions thereof.